这篇文章主要为大家展示了“MySQL 5.5如何删除索引”，内容简而易懂，条理清晰，希望能够帮助大家解决疑惑，下面让小编带领大家一起研究并学习一下“MySQL 5.5如何删除索引”这篇文章吧。

我们提供的服务有：成都做网站、网站设计、微信公众号开发、网站优化、网站认证、金沙ssl等。为上千余家企事业单位解决了网站和推广的问题。提供周到的售前咨询和贴心的售后服务，是有科学管理、有技术的金沙网站制作公司

mysql> show keys from dept2;
+-------+------------+-----------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name              | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+-------+------------+-----------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| dept2 |          0 | PRIMARY               |            1 | deptno      | A         |           4 |     NULL | NULL   |      | BTREE      |         |               |
| dept2 |          1 | idx_dept2_deptno      |            1 | deptno      | A         |           4 |     NULL | NULL   |      | BTREE      |         |               |
| dept2 |          1 | idx_dept2_report_date |            1 | report_date | A         |           4 |     NULL | NULL   | YES  | BTREE      |         |               |
+-------+------------+-----------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
3 rows in set (0.00 sec)

方法①

mysql> drop index idx_dept2_deptno on dept2;
Query OK, 0 rows affected (0.02 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> show keys from dept2;
+-------+------------+-----------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name              | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+-------+------------+-----------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| dept2 |          0 | PRIMARY               |            1 | deptno      | A         |           4 |     NULL | NULL   |      | BTREE      |         |               |
| dept2 |          1 | idx_dept2_report_date |            1 | report_date | A         |           4 |     NULL | NULL   | YES  | BTREE      |         |               |
+-------+------------+-----------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
2 rows in set (0.00 sec)

--方法②

mysql> alter table dept2 drop index idx_dept2_report_date;
Query OK, 0 rows affected (0.05 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql> show keys from dept2;
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| dept2 |          0 | PRIMARY  |            1 | deptno      | A         |           4 |     NULL | NULL   |      | BTREE      |         |               |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
1 row in set (0.00 sec)

以上是“MySQL 5.5如何删除索引”这篇文章的所有内容，感谢各位的阅读！相信大家都有了一定的了解，希望分享的内容对大家有所帮助，如果还想学习更多知识，欢迎关注创新互联行业资讯频道！

网站栏目：MySQL5.5如何删除索引
网站URL：http://myzitong.com/article/jogidi.html